ナカヤマ　ヒサコ   Hisako Nakayama   中山　寿子    所属   医学部 医学科    職種   准教授
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Common Sensory Inputs and Differential Excitability of Segmentally Homologous Reticulospinal Neurons in the Hindbrain
掲載誌名	正式名：The Journal of neuroscience : the official journal of the Society for Neuroscience 略　 称：J Neurosci ISSNコード：02706474/15292401
掲載区分	国外
出版社	the Society for Neuroscience
巻・号・頁	24(13),pp.3199-3209
著者・共著者	NAKAYAMA Hisako†, ODA Yoichi*
担当区分	筆頭著者
発行年月	2004/03
概要	In the hindbrain of zebrafish and goldfish, reticulospinal (RS) neurons are arranged in seven segments, with segmental homologs in adjacent segments. The Mauthner cell (M-cell) in the fourth segment (r4) is known to trigger fast escape behavior. Its serial homologs, MiD2cm in r5 and MiD3cm in r6, are predicted to contribute to this behavior, which can be evoked by head-tap stimuli. However, little is known about their input–output properties. Therefore, we studied afferent projections from the auditory posterior eighth nerve (pVIIIn) and firing properties of MiD2cm and MiD3cm for comparison with the M-cell in adult goldfish. Labeling of RS neurons and the pVIIIn afferents with fluorescent tracers showed that the pVIIIn projected to r4–r6. Tone burst and electrical stimulation of the pVIIIn evoked EPSPs in the M-cell, MiD2cm, and MiD3cm. Stepwise depolarization typically elicited a single spike at the onset in the M-cell but repetitive spiking in MiD2cm and MiD3cm. This atypical property of the M-cell was mediated by dendrotoxin-I (DTX-I)-sensitive voltage-gated potassium channels together with recurrent inhibition, because combined application of DTX-I, strychnine, and bicuculline led to continuous repetitive firing in M-cells. The M-cell but not MiD2cm or MiD3cm expressed Kv1.2, a DTX-I-sensitive potassium channel subunit. Thus, the M-cell and its segmental homologs may sense common auditory information but send different outputs to the spinal circuits to control adaptive escape behavior.
DOI	10.1523/JNEUROSCI.4419-03.2004
PMID	15056699